Nesta tese é apresentado um novo método de desmontagem das placas de circuito impresso obsoletas ou defeituosas, provenientes de resíduos de equipamentos eletroeletrônicos, para aplicação no processo de reciclagem. A desmontagem tem por objetivo segregar a PCI para que o material reciclado apresente maior pureza, bem como facilitar as etapas posteriores no processo de reciclagem. A desmontagem proposta é classificada como automática, simultânea e destrutiva. O método apresentado não requer o uso de tecnologias avançadas e de alto custo. Para aplicação deste método foi desenvolvido um protótipo que utiliza aquecimento do ar para derretimento da solda e força centrífuga para remoção dos componentes. O desenho deste equipamento permite a separação da PCI em 3 partes distintas: substrato, solda e componentes eletrônicos. Para a desmontagem no protótipo foram usadas placas marrons de fontes de alimentação, e placas verdes de memórias tipo RAM, com substrato de fenolite e de fibra de vidro respectivamente. A desmontagem foi realizada com sucesso em ambos os casos. Para as placas pesadas ou marrons, a faixa de operação que apresentou maior taxa de recuperação de solda (entre 2,2 e 2,8% do peso da PCI) e de componentes (entre 60 e 80% do peso da PCI) situa-se entre 200 e 206°C e 900 rpm. Para placas leves ou verdes, a desmontagem deve se situar entre 210 e 225°C e 900 rpm, sendo a quantidade de solda recuperada inferior a 1% e a de componentes aproximadamente 32% do peso da PCI. A liga de solda recuperada dos dois tipos de placas possui contaminação abaixo de 3%, teor semelhante à da borra proveniente de processos industriais de soldagem e que é utilizada como matéria prima. / In this work, is presented a new method for disassembly of obsolete or defective printed circuit board, from waste of electrical and electronic equipmente, for use in recycling. Disassembly objetives separate PCB to achives purer recycled material as well facilited the subsequent step in recycling process. Proposed disassembly is classified as automatic, simultaneous and destructive. The presented method doesn\'t required the use of advanced and expensives technologies. For this method, a prototype was developed. It utilizes centrifugal force and air heating for solder melting and components removal. Design of the prototype allows separation of PCB in 3 parts: substrate, solder and electronics components. Very low grades boards of paper laminated phenolic resins, from power supply of computers was used, as well as very high grade boards from RAM memory, made of fiberglass. Disassembly was sucessfully for both cases. For very low grade boards, operation range which has a greater amount of recovered solder (between 2,2 and 2,8% of weight of PCB) and components (between 60 and 80% of weight of PCB) is inside the range of temperature of 200 and 206°C and 900 rpm. For very high grade boards, disassembly is inside the range of temperature of 210 and 225°C and 900 rpm, with quantity of recovered solder under 1% and components aproximatelly 32% of weight of the PCB. Recovery solder for the two kinds of PCB has a contamination under 3%, similar to spare from industrial welding process, used as input in the production of new solders.

This thesis investigates the detection and classification of small boats using a passive sonar system. Noise radiated from a small boats consists of broadband noise and harmonically related tones that correspond to parameters in the boats engine and propeller. A novel signal processing method for detection and discrimination of noise radiated from small boats has been developed. There are two main components to the algorithm. The first component detects the presence of small boats by the harmonic tonals radiated from the boat propeller and engine. The second component was designed to extract the a signature from passive sonar data. The Harmonic Extraction and Analysis Tool (HEAT) was designed to estimate the fundamental frequency of the harmonic tones, track the fundamental frequency using a Kalman filter, and automatically extract the amplitudes of the harmonic tonals to generate a harmonic signature for the boat. The algorithm is shown to accurately extract theses signatures, and results show that the signatures are unique enough that the same boat passing by the hydrophone multiple times can be recognized.

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Thesis submitted in compliance with the requirements for the Master's Degree in Technology: Electrical Engineering - Light Current, Durban University of Technology, Department of Electronic Engineering, 2008. / Linear control systems can be easily tuned using classical tuning techniques such as the Ziegler-Nichols and Cohen-Coon tuning formulae. Empirical studies have found that these conventional tuning methods result in an unsatisfactory control performance when they are used for processes experiencing the negative destabilizing effects of strong nonlinearities. It is for this reason that control practitioners often prefer to tune most nonlinear systems using trial and error tuning, or intuitive tuning. A need therefore exists for the development of a suitable tuning technique that is applicable for a wide range of control loops that do not respond satisfactorily to conventional tuning. Emerging technologies such as Swarm Intelligence (SI) have been utilized to solve many non-linear engineering problems. Particle Swarm Optimization (PSO), developed by Eberhart and Kennedy (1995), is a sub-field of SI and was inspired by swarming patterns occurring in nature such as flocking birds. It was observed that each individual exchanges previous experience, hence knowledge of the “best position” attained by an individual becomes globally known. In the study, the problem of identifying the PID controller parameters is considered as an optimization problem. An attempt has been made to determine the PID parameters employing the PSO technique. A wide range of typical process models commonly encountered in industry is used to assess the efficacy of the PSO methodology. Comparisons are made between the PSO technique and other conventional methods using simulations and real-time control.

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Thesis (M.S.)--University of Missouri--Rolla, 2007. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed February 5, 2008) Includes bibliographical references (p. 82).

Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 215-220).

Dissertation (Ph.D.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references (p.91-95).

Thesis (Ph. D.)--University of Texas at El Paso, 2008. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.